PROJECT SUMMARY/ABSTRACT For the 5.3 million older Americans with Alzheimer?s disease and related dementias (ADRD), end-of life-care is increasingly marked by intensive medical treatments that are goal-discordant, confer no benefit, and likely causes harm. Compared to a decade ago, older adults with advanced dementia in the United States (US) are twice as likely to receive mechanical ventilation and be admitted to the ICU without substantial improvement in survival. There is a lack of research describing the systemic and cultural drivers of burdensome ICU care, which we define as ICU admission, ICU level treatments such as vasopressors or mechanical ventilation, and resuscitation amongst older adults with ADRD near the end of life. Comparisons between the US and the United Kingdom (UK), a country that has significantly lower rates of terminal ICU hospitalization than the US, are useful in determining modifiable drivers of burdensome ICU care. By identifying practices that are common or accepted in the UK, but not found in the US, we can bring a different perspective onto typical practices in the US and identify innovative practices that exist in the UK that could be introduced in the US context to modify the American culture of burdensome ICU care. The long-term goal is to design, pilot, and implement hospital systems-level interventions that successfully shift institutional culture to mitigate burdensome treatments for older adults with ADRD near the end of life. The objective of this project is to identify factors at the institutional level that contribute to burdensome ICU treatments in older adults with ADRD near the end of life. The first aim of this project is to identify institutional, clinician, patient, and family factors that contribute to burdensome ICU treatments in older adults with ADRD near the end of life in the US and United Kingdom (UK). This will be accomplished through a comparative ethnography (observations) at two hospitals in the US (UCSF and UCLA), and two in the UK (King?s College Hospital and Princess Royal University Hospital). The observations will focus on of the day-to-day activities and behaviors of individuals involved in the care of older adults with ADRD such as ward rounds, family meetings, and treatment discussions. The project?s second aim identifies promoter and inhibitors of burdensome ICU treatments in older adults with ADRD near the end of life through semi-structured in-depth interviews with key stakeholders at all levels of the healthcare system. The proposed research is innovative because it will be the first rigorously designed, in-depth qualitative study examining cultural and systemic factors related to burdensome ICU care between the US and UK. This study is significant because it will uncover previously uncharacterized cultural and systemic factors that contribute to burdensome ICU care, which can be used to develop targeted interventions to mitigate burdensome care in older adults with ADRD.